I need to know number 2 3 4 and 5

What is the mass of 8 moles of sodium atoms

Identify the electromagnets with poles that are reversed from the electromagnet shown above

Question 3(multiple choice worth 4 points) (04.04 lc) what does it mean when an element is reduced? it empties a valance shell, reducing its atomic radius. it gains electrons, reducing its overall charge. it increases electronegativity, reducing its ability to bond. it loses electrons, reducing its electron number.